Electromagnetic telegraph.



D. M. BLISS. 4 BLECTROMAGNETIC TBLBGRAPH.

I, APPLICATION IILED JULY 2, 1909.

1,102,234, l, PateptedJulymsm,

invento-z,

ono ld M. HSS

'mitted from the sending station to there f mature are connected tosuitable indicating maas Partnr oiariioEl DONALD M. BLISS, yOFSTA'MFORD, CONNECTICUT, 4.ASSIGINOR OF T WO-FIFTHS TO CHARLES J.HENSGHEL, OF 'NEW YORK, F BROOKLYN, 'NEW YORK.

N. Y.,All.\lllD` ON,E-FIFTH TO FRANK W. WOOD,

ELECTROMAGNETIC TELEGRAPH..

1,102,234. Specification of Letters Patent. Patented July 7, 1914.

Application filed July 2, 1.9()9.; SeriaLNo. 505,776.

To all whom t may concern Be it known that I, DONALD. Mf BLISS, acitizen of the Dominion of Canada, residing at Stamford, in the countyof Fairfield and State of Connecticut, haveinvented new and usefulImprovements in Electromagnetic Telegraphs, of which the following is aspecification.

My invention relates to `that class of elec-` tromagnetictelegraphs-which are commonly used on shipboard and at other placeswhere` it is desired that a number of successive indications, whichA mayor may not differ in' character, are desired to be transmitted from onepoint to another.. Many such devices have been designed and many haveproven practical. A Agreat number of these, however, are somewhatcomplicated and are made' up of a number of partswhich are ex pensive tomanufacture, difficult to assemble, or to adjust, and when adjusted arenot easily kept in adjustment.`

The prime object of my invention is tor produce a device for thetransmission of intelligences which is exceedingly simple, consists ofbut few elementary parts, is easy to adjust, and is as durable asservice requires.

'lhe device which I have produced is read ily adjusted, and whenadjusted to transmit the proper intelligences remains as adjusted untilthat adjustment is changed by the operator. In other words, theadjustment is permanent, and signals can be thus trans ceiving stationin absolutely correct and accurate manner. i

In carrying out my invention I make use of a source o't' alternatingcurrent of constant potential to setup an alternating current magneticfield of substantially constant intensity. In this field thus set up Imount an armature, so that its angular, position with respect to themagnetic field can be changed at will. The terminals ot thisarinstruments in such a manner that as the angular position of thearmature is varied, the extent o'tf variation is shown by the indieating instrun'ients. I place the magnetic field with the rotatablearmature at a sending station and the indicating instruments at areceivingstation, and by varying the angular position or' the armaturewith rcspect to the field in which it is placed transinit lintelligencesfrom the one point to the other.

For a full understanding of my invention, reference is to be had to theyaccompanying sheet of drawing `which shows diagrammatieally. thesending and receiving apparatus together with the interconnectingcircuits.

` 1 is a U-shapedmagnetic core on the yoke of .whichis mounted anenergizing coil 2. supplied with lalternating current at substantiallyyconstant potential from the generatorB. The poles ofy this magneticcore are y bored out on the arc of a circle in order to accommodate thearmature 4, which is suitably mounted and adapted to be rotated betweenthem. This arm'ature consists of a core 5 which is longitudinallyslotted or .otherwise cut to receive a coil G, and is provided with athumb piece 7, whereby it may be turned at will. Suitably mounted on thearmature if are two semi-circular contact strips 8 and 9, which areconcentric with the armature and extend through an are oi 180 degreesfrom a diameter passing axially of the coil G. A pair of brushes orfixed contarts/1() are so mounted as to bear on these contact strips andon a line approximately eonnecting'the renters of the poles of themagnet 1. Diaxietrically opposite the pair of fixed contacis or brushes10 is a second pair of fixed contacts or brushes l1 adapted to contactwith the strips S and 9 when the armature 4l has been turned through 90degrees. A, pointer 12 moving over a scale 13 is attached tothe armaturein such a manner that as the armature is turned its angular position isindicated upon the scale.

The device thus tar described constitutes the transmitting device whichis located. at the sending station.

Connected one to each set of brushes 10 and i1 1 are two alternatingcurrent indicating instruments 14. and 15, which are shown as mountedupon a common base with their pointers toward each other and moving overa common scale plate. -Thesc two instruments constitutey together thereceiving device and are located at the receiving station.

- scales of the receiving instruments 14 and 15 are also graduated toindicate from zero to one hundred. The scale of instrument 14 indicatesfrom zero to fifty, and the scale of instrument 15 indicates from fiftyto one hundred in the reverse direction. The pointer 12 of thetransmitting instrument is so located with respect to the armature coil'6 that it points to zero on the scale when the axis of the coil 6 is atright angles to the magnetic iield produced by the'coil 2 and f core 1.`The parts being in the position shown, and it being'desired to cause thereA ceiving instrument to indicate 2() for instance, the thumb piece 7is grasped and the armature 4 turned'with its coil `6 inthe magneticfield until the pointer` 12 reaches 20. J In the position shown the axisof coil 6 being at right angles to the magnetic eld nocurrent will begenerated within it. But the moment its coil is, turned so that its axisis at an angle less than a right angle with the magnetic field, currentis generated in thiscoil, and the current generated is proportionalapproximately, and can be made by suitable proportioningand placing ofthe winding or by suitable forming the poles of core 1 absolutelyproportional. 'Ihe current thus produced passes out through brushes10'and over wires connected to themV to instrument 14, which willindicate 2O on its scale. In case it is desired that -the receivinginstrument indicate 80, the armature 4 is turned to the right until thepointer 12 indicates 80, when the pointer of instrument l5 will indicate80, for it will be observed that as the pointer 12 passes the mid-pointof its scale 13, e'. e., passes A onthatscale, the contact strips 8 and9 have come into engagement with the brushes 11, which are connected toinstrument 15. Just at the moment of passage over the 50 indication, orthe midpoint of the scale, both instruments .14 and 15, read 50,.as bothsets of brushes 10 and 11 are in Contact with the strips 8 and 9 and theelectro-motive force and hence the current generated in the coils 6 isat a maximum, the axis of the coil being parallel to the line connectingthe mid points of the poles of magnet 1 and all of I the lines of fnrcepassing through the coil.

After the 50 point is passed and movement 4is made toward the 80 point,the strips 8 and 9 pass out from under brushes 10 and hence instrument14 indicates Zero, while instrument 15 moves backward from the 50 pointwhich it reached the moment contact was made with strips 8 and 9 andtoward the starting or zero point.

80 indication. The reason for this is apparent when we remember that theelectromotive force in coil 6 is zero in the position shown, thenmaximum at the 50 indication, and then reaches zero again at the onehundred indication, 180 degrees from the It will thus be observed that Ihave produced an exceedingly simple and efficient apparatus. sistsessentially of two elements and has no parts which are liable to getoutof order. The transmitting device has but few contacts and thereceiving device has'none at all, current being led directly into theinclined coils of the receiving instruments.

The transmitting device con- By using the two semi-circular contactstrips 8 and 9 and using two indicating in.

struments, I have increased'the range of indication of my apparatus from90 degrees to 180 degrees. It is, of course, obvious that in case I useonly one indicating in# strument, it would b'e impossible *tof tellWhether the armature was rotated from zero to ninety degrees, and thenback again, or from zero to 180 degrees, as the elect-roT motive forcebuilds up according to a sine wave from zero to 90 degrees, and thenfalls again to 180 degrees. I could,'of course, have both instruments toindicate at once, but by extending the contact strips 8 and 9 throughonly 180 degrees I use only one instrument at a time, and confusion isthereby avoided.

Of course it is understood that suitable stops may be provided to engagethe armature 4 to hold it in adjusted positions and to prevent itsrotation to an angle greater than 180 degrees. l

It is also evident that I may calibrate and mark the scales of theinstruments to give whatever indications I may desire, such as tneletters of the alphabet, speed indications, v

time indications, etc.

I may also useI a magnetic field other than alternating, such forinstance,vas a pulsating magnetic field or a variable field of 'othernature.

While I have described the best form of my invention now known to me, Idesire to have it understood that many modifications may be made thereinwithout departing from the generic spirit, and I desire to cover by theannexed claims all such modifications.

What I claim is,-

' 1. An' electro-magnetic telegraphl comprising an'armature in analternating magnetic field, means for moving the armature to any one .ofanumber of positions in said. field, two independent current collectingde-v vices in successive operative relation to said armature, and anindicating instrument connected to each of said collecting devices.

2. An electro-magnetic telegraph comprising an armature in analternating inagnetie field, means for moving the armature to any one ofa number of positions in said field, two indicating instruments, andmeans 'for successively passing current induced in said arn'iaturethrough both instruments.

3. An electro-magnetic telegraph comprising an armature in analternating magnetic field, means 'for moving the armature to any one ofa plurality of' positions in Said field, two indicating instruments, andcurrent eollecting devices which pass current from said armature firstthrough one indicating instrument and then through the other.

4t. An electro-magnetic telegraph, comprising mechanism for producing analternating field, a rotatable ari'nature located within said field,means for turning said armature to any one of a number of angularpositions in said field, a pair of separate sets of collecting devicesassociated with said armature and so positioned as to be broughtsuccessively into electrical communication therewith as said armature isthus turned, and a pair of indicating instruments each connected withone set only of said collecting devices so that said instruments areenergized one after the other as said armature is turned, one of saidinstruments being calibrated to indicate a certain range of' angularpositions of said armature, and the other indicating instrument beingcalibrated to indicate another range thereof', said last mentioned rangebeing practically a continuation of said first mentioned range.

5. In an electro-magnetic telegraph, an'

armature rotatable in an alternating magnetic field, means for movingthe armature to 'any one of a number of positions in said field, currentcollecting devices in operative relation to said armature 4andcomprising a pair of' movable contacts and two pairs of fixed contactsangularly spaced apart with respect to the center of rotation of saidarmature, two indicators, and means connecting each indicator to a pairof fixed contacts.

(3. In an electro-magnetic telegraph, `an armature in an alternatingmagnetic field, means for moving the armature to any one of' a number ofpositions in said field, eurrent collecting devices in operativerelation to said armature and comprising a pair of semi-circular movablecontacts and two pair of fixed contacts angularly spaced apart, twoindicators, and means connecting each indi fator to a pair of fixedcontacts.

7. i'n electro-magnetic telegraph, comprising a transmitter by which acurrent rising from minimum to maximum and dropping from n'iaximum tominimum may be transmitted by operation of the transmitter in the samedirection, a current operated receiving device comprising a receivinginstrument adapted to give indications over a certain range during therisc of current from minimum to maximum, and means giving an additional`ange of indication in continuance of the aforesaid range during thefollowing drop of current from maximum to minimum when the transmitteris moved further in the same direction.

S. In an electro-niagnetic telegraph, a. sending instrument whichproduces a cui'- rent off increasing intensity to maximum thendecreasing intensity to minimum, two receiving instruments, andindependent current collecting devices in successive operative relationto said sending instrument which first pass a. current increasing fromminimum intensity to maximum through one receiving instrument and thenpass a current decreasing from maximum intensity to minimum through theother receiving instrument.

9. In an electric teleg'aph, a transmitter, a receiver,- said receivercomprising a compound device for indicating intelligences consisting oftwo receiving instruments, connections whereby one of them givesindications up to a certain maximum value over a certain `angeconnections whereby another of them gives indications in continuation ofthe indications of said first instrument. 4

10. An electro-magnetic telegraph consisting of a transmitter comprisingan armature, means for producing a variable inagnetic field in whichsaid armature is placed, and means for changing the relative position ofthe armature with respect to the magnetic field, and a receiving devicecomprising a compound indicating instrument made up of two indicatingdevices, and connections between said receiving instrunient and saidtransmitter whereby one device indicates the extent of its range and theother device thereafter gives indications in continuation of theindications of the one.

11. An electro-magnetic telegraph comprising a transn'iittcr by which acurrent rising from minimum to maximum and dropping from maximum tominimum may be 'transmitted a current operated receiving instrumentcomprising an indicating device having a scale which gives increasingindications for increasing values of current from minimum to maximum,and a second indicating device which gives increasing indications fordecreasing values of current after the maximum value has been passed.

12. An electro-magnetic telegraph consisting of a transmitter by which acurrent rising :from minimum to maximum and dropping from maximum tominimum may be transmitted, and a current operated receiving instrumentcomprising an indicating device which indicates through a certain rangefor values ofcurrent from minimum A to In testimony whereof I havehereunto setmuximum, and a second indicating devlce -my hand in presenceof two subsorlbmg Wililp which gives indications 1n continuation ofnesses.

Ache indications of the first device after the maximum value of thecurrent is passed, and Y DONALD M BLISS' means whereby said device iscaused to indi- Witnessesz cate after the first device has reached itsO'ivro HENSOHEL,

maximum. (J1-LAMES F. LEINING

